1. Field of the Invention
The present invention relates to substrate processing apparatus and, more particularly, to a substrate processing apparatus with a removable component module.
2. Brief Description of Related Developments
Continuous demand by consumers for ever cheaper electronic devices has maintained pressure on manufacturers of the device to improve efficiency. Indeed, in the current market place, many of the devices, and to a much greater extent the electronic and semiconductor components used in the devices, have become commodities. The desire of manufacturers of electronic and semiconductor device to increase efficiency manifests itself at all levels, but is of special significance in the design, construction, and operation of fabrication facilities or fabs. One unit by which to measure the efficiency of a given fab may be the throughput per unit of area (e.g. throughput per FT2). As may be realized from this unit of measure, the fab efficiency (i.e. higher throughput/ft2) may be increased by any means that raise the production rate per available ft2 of fab space. One means to readily achieve this is by packing as many substrate processing stations as possible in the available fab space. An example of a conventional layout of a substrate processing facility is illustrated in FIG. 1.
The processing stations in the FAB facility 1 may be arranged in any manner, and are shown in FIG. 1 arranged in processing bay matrix arrangement. The FAB processing stations may be of any suitable kind and may include for example substrate processing tools 3, (capable of carrying out any desired semiconductor substrate manufacturing process such as material deposition, etching, baking, cleaning, polishing), stackers 5 (for holding FAB transfer pods, substrate cassettes or substrates), and sorters 4 (for sorting substrates according to desired process recipe in transfer pods or cassettes). The processing facility may also have a FAB material handling system 7 for handling substrates, either in transfer pods (such as front opening unified pods (FOUPs) or standard machine interface (SMIF)), cassettes or individually, between the various processing stations in the FAB 1. The handling system 7 may have intrabay sections 7A-7D connecting processing stations located in the FAB bays, and interbay sections 7E connecting the intrabay sections. As may be realized from FIG. 1, by increasing the density of processing stations in the FAB 1, the FAB is capable of fabricating a greater number of substrates at any one time with a corresponding increase possible in FAB throughput. Naturally, the result of an increase in processing facility density in the FAB is that the processing stations become more compacted together with a commensurate loss in access space to each processing station. The loss of access to the respective processing stations impairs the ease of installation of automation components, such as substrate transport apparatus, aligners, load port modules, into the substrate processing stations. To overcome the installation restrictions due to limited access space, FAB builders have sought more integration of automation components so they may be installed as an automation unit into the respective processing stations. International Publication No. WO03/009347, dated 30 Jan. 2003, discloses an example of a conventional integrated system for workpiece handling for the front end of a processing tool. The conventional system comprises a rigid member, to which front end components including the load port assemblies, pre-aligners, and handling robot are mounted, and which in turn is mounted to the front end of the tool. Another example of a conventional unified spine Structure that environmental front end module (EFEM) components are mounted to is disclosed in International Publication No. WO03/019630, dated 6 Mar. 2003. As evident from the aforementioned examples, conventional integrated automation platforms remain substantially customized to the particular processing stations to which given integrated automation platforms are mounted. As in the case of the installation of separate automation components to a processing station (each component of which is aligned to the unique reference system of the processing station within alignment system accounting for unique variances in component and station), the automation components of the conventional integrated automation platform are aligned to the processing station accounting for variances in the automation components, the integrated platform itself and also the processing station. Hence, the mounting and alignment of the conventional integrated automation platforms to processing stations remains dependent on a number of fabrication variances and each installation is substantially a custom installation. Consequently, conventional integrated automation platforms are not readily swapped between substantially similar processing stations because installation to a different station involves complex and time consuming alignment to the given station. Further, as also evident from the noted examples, the conventional integrated automation platforms are not self standing, using ancillary supports to maintain a stable position for mounting to the processing station. Nor are the conventional integrated automation platforms capable of self or independent transport. Hence, in order to install a conventional integrated automation platform to a processing station dedicated handling equipment is used to support and transport the conventional platform into position and to allow alignment of the automation components to the processing station reference systems. The use of dedicated handling equipment increases the space envelope demand to accomplish installation and removal thereby limiting processing station density in the FAB.